The present invention relates to a computer system, in particular a personal computer system having a bus system such as a PCI/PCI-X bus or similar configurable bus system.
Personal computers, servers, laptop computer with docking stations, and other computer systems having a bus system for adapter cards are well known in the art. These computer systems typically include a CPU coupled through a cache bridge logic to a main memory. The cache bridge logic also typically couples to a high bandwidth local expansion bus, such as the peripheral component interconnect (PCI) bus or the VESA (Video Electronics Standards Association) VL bus. Typically, a PCI bus comprises two different bus speeds such as 33 MHz and 66 MHz. FIG. 1 shows a plurality of slots (bus sockets) 110-170 which are in general placed on a mother board 100 for coupling with the bus. Sockets 120-170 are configured to receive standard 64 bit PCI adapter cards whereas socket 110 receives a standard 32 bit PCI card. To be compatible with multiple adapter cards inserted into the system the following principle applies for a PCI bus system. Whenever a user inserts an adapter card into the PCI bus sockets the system bus adapter system runs at the speed defined by the slowest adapter card inserted into the bus system.
Another bus with extended capabilities is a newly developed extended peripheral component interconnect (PCI-X) bus. This bus system addresses the need for increased bandwidth of PCI Devices. The PCI-X standard enables the design of systems and devices that can operate at speeds significantly higher than known systems with their respective specification allow. Just as importantly, it provides backward compatibility by allowing devices to operate at conventional PCI frequencies and modes when installed in conventional systems. Devices can be designed to meet PCI-X requirements and operate as conventional 33 MHz and 66 MHz PCI devices when installed in those systems. Furthermore, this bus allows high speed transmission modes, P for example at 133 MHz. Similarly, if conventional PCI devices are installed in a bus capable of PCI-X operation, the clock remains at a frequency acceptable to the conventional device, and other devices on that bus are restricted to using conventional protocol. This high degree of backward compatibility enables the easy migration of systems and devices to bandwidths in excess of established bus systems with limited bandwidths.
Thus, PCI, PCI-X and similar bus systems are defined by the slowest card inserted with regard to their transmission speed. Modern computer systems provide multiple system busses, for example two independent PCI or PCI-X busses. The advantage of having multiple system busses is that in case two busses are provided, one can be used for slower system adapter cards and one can be used for the faster adapter cards. However, a user not familiar with the technology will not recognize which adapter card that has already been inserted provides what transmission speed capabilities. Even so a user not skilled in the art is certainly able to extend a computer system by inserting an adapter card, the user might not know which bus is the appropriate bus for the respective adapter card. The user will of course know the speed of the new card to be inserted into the bus system but will probably not remember the respective speed of already inserted cards. Furthermore, systems usually do not indicate which socket is assigned to which of the independent PCI busses.
U.S. patent application Ser. No. 09/769,799 xe2x80x9cRA system and for method for configuring an I/O busxe2x80x9d, filed on Jan. 25, 2001 by David Locklear and Michael Wright and assigned to Dell Corp. describes a remedy to this problem. According to this application the mother board of a computer system comprises light emitting diodes associated to each slot of a PCI bus to indicate whether an adapter card inserted into the slot is limiting the transmission speed on the bus associated to the respective slot. However, this system still does not clearly inform a user what specific configuration has been selected to a specific slot. Furthermore, valuable real estate area on the mother board has to be used to place indicators such as light emitting diodes.
Therefore, a need for an improved bus system exists which overcomes the above mentioned problems. In one embodiment of the present invention a computer system including a circuit board comprises a bus system for transmitting address, data and control signals with selectable bus configuration, a plurality of bus sockets on the circuit board for connecting an adapter card with the bus signals, whereby the specification of the adapter card determines the configuration of the associated bus, and an indicator for the bus indicating the configuration, wherein the indicator is integrated in the socket.
A method of indicating a bus speed within a computer system having a system bus with a plurality of sockets for receiving system adapter cards, whereby the specification of said adapter cards determines the bus configuration, and whereby said socket comprises an integrated indicator, comprises the steps of:
inserting an adapter card in one of the sockets;
determining and setting the bus speed for all sockets associated to the bus;
indicating the bus configuration for the bus by the indicator.
In another embodiment a socket for a computer bus system for connecting a plurality of address, data and control signals to an adapter card which can be plugged into said socket, comprises an indicator for indicating a bus configuration.
The indicator may indicate the current bus speed and/or other configuration parameters, such as bus width, transmission modes, etc. Furthermore, a socket for the bus system may have an integrated driver and control circuit for driving the indicator. The indicator can be a light diode or a display, such as an alphanumeric or numeric LCD or LED display. For a hot-plug feature an activation switch and further indicators may be provided. The bus system can be a PCI and/or PCI-X bus or any other configurable bus system. The socket can be designed to be equal in size compared to a socket according to the prior art. However, in another embodiment, the socket may be enlarged to receive the indicator. In yet another embodiment, the socket may have left and right side walls, whereby an upper portion of one of the side walls is extended outwards to receive the integrated indicator. In yet another embodiment, only a partial extension of a side wall may be provided to receive the integrated indicator and/or switch.
The different exemplary embodiments according to the present invention provide a user with all necessary information to insert an adapter card in an appropriate bus socket whereby precious real estate on a system board is preserved. The socket according to the present invention may be equal in size to sockets according to the prior art or designed in a way that the design of a previously designed circuit board which receives such a bus socket does not have to be redesigned. Modification to a bus socket to be able to integrate an indicator can be performed according to the present invention to allow placement of devices close to sockets according to the prior art.
Other technical advantages of the present disclosure will be readily apparent to one skilled in the art from the following figures, descriptions, and claims. Various embodiments of the present application obtain only a subset of the advantages set forth. No one advantage is critical to the embodiments.